Nutrient Deficiency Conditions Research Articles

M1A regulator-mediated methylation modification patterns correlated with autophagy to predict the prognosis of hepatocellular carcinoma.

N1-methyladenosine (m1A), among the most common internal modifications on RNAs, has a crucial role to play in cancer development. The purpose of this study were systematically investigate the modification characteristics of m1A in hepatocellular carcinoma (HCC) to unveil its potential as an anticancer target and to develop a model related to m1A modification characteristics with biological functions. This model could predict the prognosis for patients with HCC. An integrated analysis of the TCGA-LIHC database was performed to explore the gene signatures and clinical relevance of 10 m1A regulators. Furthermore, the biological pathways regulated by m1A modification patterns were investigated. The risk model was established using the genes that showed differential expression (DEGs) between various m1A modification patterns and autophagy clusters. These in vitro experiments were subsequently designed to validate the role of m1A in HCC cell growth and autophagy. Immunohistochemistry was employed to assess m1A levels and the expression of DEGs from the risk model in HCC tissues and paracancer tissues using tissue microarray. The risk model, constructed from five DEGs (CDK5R2, TRIM36, DCAF8L, CYP26B, and PAGE1), exhibited significant prognostic value in predicting survival rates among individuals with HCC. Moreover, HCC tissues showed decreased levels of m1A compared to paracancer tissues. Furthermore, the low m1A level group indicated a poorer clinical outcome for patients with HCC. Additionally, m1A modification may positively influence autophagy regulation, thereby inhibiting HCC cells proliferation under nutrient deficiency conditions. The risk model, comprising m1A regulators correlated with autophagy and constructed from five DEGs, could be instrumental in predicting HCC prognosis. The reduced level of m1A may represent a potential target for anti-HCC strategies.

The Effect of Nutrient Deficiencies on the Annual Yield and Root Growth of Summer Corn in a Double-Cropping System.

The North China Plain has a typical winter wheat-summer corn double-cropping pattern. The effects of nutrient deficiency conditions on the root characteristics and yield of summer corn in the double-cropping system were studied for four years. Long-term monotonous fertilization patterns undermine crop rotation systems and are detrimental to the sustainability of agricultural production. To complement the development of rational fertilization strategies by exploring the response of crop rotation systems to nutrient deficiencies, an experiment was conducted in a randomized complete block design consisting of five treatments with three replicates for each treatment: (1) an adequate supply of nitrogen and phosphate fertilizers and potash-deficient treatment (T1); (2) an adequate supply of nitrogen and potash fertilizers and phosphorus-deficient treatment (T2); (3) an adequate supply of phosphorus and potash fertilizers and nitrogen-deficient treatment (T3); (4) nutrient-sufficient treatment for crop growth (T4); and (5) no-fertilizer treatment (CK). The results showed that different nutrient treatments had significant effects on the root length density (RLD), root surface area density (RSAD), and root dry weight density (RDWD) in summer corn. At the physiological maturity stage (R6), the root indexes of RLD, RSAD, and RDWD were significantly higher in the 0-20 cm soil layer in T4 compared to CK, with an increase of 86.2%, 131.4%, and 100.0%, respectively. Similarly, in the 20-40 cm soil layer, the root indexes of T4 were 85.7%, 61.3%, and 50.0% higher than CK, with varied differences observed in the other nutrient-deficient treatments. However, there was no significant difference among the treatments in the 40-60 cm layer except for T4, whose root index showed a difference. The root fresh weight and root dry matter in T4, T3, T2, and T1 were increased to different degrees compared with CK. In addition, these differences in root indexes affected the annual yield of crops, which increased by 20.96%, 21.95%, and 8.14% in T4, T2, and T1, respectively, compared to CK. The spike number and the number of grains per spike of T4 were 10.8% and 8.3% higher than those of CK, which led to the differences in summer corn yields. The 1000-kernel weight of T4, T2, and T1 were 9.5%, 8.8%, and 7.4% higher than that of CK, whereas the determining nutrient was nitrogen fertilizer, and phosphorus fertilizer had a higher effect on yield than potassium fertilizer. This provides a theoretical basis for the effect of nutrient deficiency conditions on yield stability in a double-cropping system.

The effect of viral infection on the Black Sea microalgae Tetraselmis viridis: the role of nutrients and copper ions.

The TvV-SM2 virus, isolated from the coastal waters of the Black Sea, causes lysis of its host, the algae Tetraselmis viridis (Chlorophyta). Under optimal conditions for nutrients, an increase in the initial abundance of algae cells by four times caused a 3-fold reduction in the latent period of viral infection. During the period of the most rapid cell lysis of T. viridis , nitrogen deficiency leads to a decrease in the average daily rate of death of cells affected by the virus by 3.2times relative to the replete conditions, while in the case of phosphorus deficiency, this process slows down by up to 2.4times. Under deplete conditions, the rate of cell death was only 34% lower than under replete conditions. The effect of copper ions (100μgL-1 ) on the viral suspension for 6h led to the complete suppression of its activity. In the presence of the host of this virus, its activity is only partially suppressed. As a result, cell lysis under the influence of a viral infection occurred in two stages. The first stage was noted only during the first 6h of the experiment. The second main stage took place within 78-170h. This study showed that in conditions of nutrient deficiency and in the presence of copper ions in seawater, the impact of viruses on microalgae will be weaker.

Transgenerational plasticity in morphological characteristics and biomass of the invasive plant Xanthium strumarium.

Transgenerational plasticity (TGP) allows a plant to acclimate to external variable environments and is a potential mechanism that explains the range expansion and invasion success of some exotic plants. Most studies explored the traits of TGP associated with the success of exotic plant invasions by comparison studies among exotic, native, invasive, and noninvasive species. However, studies on the TGP of invasive plants in different resource environments are scarce, and the biological mechanisms involved are not well understood. This study aimed to determine the role of TGP in the invasiveness of Xanthium strumarium in northeast China. We measured the plant morphology of aboveground parts and the growth of three generations of the invader under different environmental conditions. The results showed that the intergenerational plasticity of X. strumarium was stronger under stress conditions. We found that the X. strumarium parent generation (F0) grown under water and/or nutrient deficiency conditions transferred the environmental information to their offspring (F1 and F2). The F1 generation grown under high-resource conditions has greater height with larger crown sizes, thicker basal diameters, and higher biomass. Both water and nutrients can affect the intergenerational transmission of plant plasticity, nutrients play a more important role compared with water. The high morphological intergenerational plasticity of X. strumarium under a pressure environment can help it quickly adapt to the new environment and accelerate the rapid expansion of the population in the short term. The root:shoot ratio and reproductive and nutrient distribution of the X. strumarium F0 and F1 generations showed high stability when the growth environment of the F0 generation differed from that of the F1 generation. The stable resource allocation strategy can ensure that the obtained resources are evenly distributed to each organ to maintain the long-term existence of the community. Therefore, the study of intergenerational transmission plasticity is of great significance for understanding the invasion process, mechanism, and prevention of invasive plants.

Effect of starvation on the performance of a biotrickling filter packed with diatomaceous earth composite fillers for xylene removal

The continuous operation of a biotrickling filter (BTF) is difficult to guarantee in industrial applications. Herein, BTF packed with diatomaceous earth-based composite fillers was investigated to treat xylene under the operating conditions of complete shutdown and nutrient deficiency. The BTF experienced complete shutdown (4 h, 8 h, 12 h, 16 h, 20 h, 2 d, and 7 d), and the removal efficiency recovered completely within 1 d of operation. The performance of the BTF was not significantly affected by 87 d of complete shutdown or 43 d of nutrient deficiency. High-throughput sequencing revealed that the diatomaceous earth-based composite filler could provide a good living environment for microorganisms and maintain microbial activity during starvation stages. The results show that the diatomaceous earth-based composite filler has great resistance to starvation.

Sugar Starvation Disrupts Lipid Breakdown by Inducing Autophagy in Embryonic Axes of Lupin (Lupinus spp.) Germinating Seeds.

Under nutrient deficiency or starvation conditions, the mobilization of storage compounds during seed germination is enhanced to primarily supply respiratory substrates and hence increase the potential of cell survival. Nevertheless, we found that, under sugar starvation conditions in isolated embryonic axes of white lupin (Lupinus albus L.) and Andean lupin (Lupinus mutabilis Sweet) cultured in vitro for 96 h, the disruption of lipid breakdown occurs, as was reflected in the higher lipid content in the sugar-starved (-S) than in the sucrose-fed (+S) axes. We postulate that pexophagy (autophagic degradation of the peroxisome-a key organelle in lipid catabolism) is one of the reasons for the disruption in lipid breakdown under starvation conditions. Evidence of pexophagy can be: (i) the higher transcript level of genes encoding proteins of pexophagy machinery, and (ii) the lower content of the peroxisome marker Pex14p and its increase caused by an autophagy inhibitor (concanamycin A) in -S axes in comparison to the +S axes. Additionally, based on ultrastructure observation, we documented that, under sugar starvation conditions lipophagy (autophagic degradation of whole lipid droplets) may also occur but this type of selective autophagy seems to be restricted under starvation conditions. Our results also show that autophagy occurs at the very early stages of plant growth and development, including the cells of embryonic seed organs, and allows cell survival under starvation conditions.

Reference gene selection for qRT-PCR analysis in the shoots and roots of Camellia sinensis var. sinensis under nutritional stresses

Quantitative real-time polymerase chain reaction (qRT-PCR) is a useful way to evaluate gene expression level, in which the selection of internal references needs to be addressed firstly. However, the stably expressed reference genes in tea plants (Camellia sinensis var. sinensis) under different nutrient deficiency has not been reported. In this study, seven candidate reference genes (i.e., ACTIN7, EF-1α, eIF-4α, GAPDH, PP2A, TBP and TIP41) were employed to evaluate their expression stability using three algorithmic programs (i.e., geNorm, NormFinder and BestKeeper) under six kinds of nutrient deficiency conditions [i.e., ammonium nitrogen (-NH4+-N), nitrate nitrogen (-NO3−-N), phosphorus (-P), potassium (-K), calcium (-Ca) and magnesium (-Mg)] in C. sinensis shoots and roots. The results showed that (1) the combinations of PP2A and ACTIN were stably expressed in shoots under -NH4+-N and EF-1α combined with PP2A and TBP were stably expressed in -NH4+-N roots or -P shoots; (2) the combinations of ACTIN and EF-1α or ACTIN and TBP were stable in shoots and roots under -NO3−-N; (3) TBP combined with EF-1α and TIP41 was stably expressed in -P roots-Ca roots; (4) eIF-4α and ACTIN exhibited stable expression in -K shoots and the combination of EF-1α and TIP41 was stable in -K roots; (5) GAPDH and EF-1α or EF-1α and eIF-4α were stably expressed in -Ca or -Mg shoots and TIP41 combined with ACTIN and eIF-4α was stably expressed in -Mg roots. Moreover, six nutrient deficiency responsive genes (i.e., CsAMT1;2, CsNRT2;6, CsPT4, CsKT8, CsCTA11 and CsMGT1) were chosen to validate the suitability of the selected reference genes, and the expression levels of these target genes showed significant difference when using the most stable single gene (or combination of genes) and the least stable gene for normalization. These results provide guidelines and facilitate the quantification of gene transcription in C. sinensis shoots and roots under macro- and medium-element deficient conditions.

Glucosinolates: Structure, classification, biosynthesis and functions in higher plants

ABSTRACT
 Objective: To analyze concepts, structure, classification, biosynthesis and functions of glucosinolates (GSLs) in higher plants.
 Design/methodology/approach: A search was performed into recent high-impact literature related to glucosinolates (GSLs).
 Results: GSLs are secondary metabolites rich in N and S. They are divided into aliphatic, aromatic, and indole GSLs depending on the amino acid from which they arise. The products of their hydrolysis, mediated by thioglucoside glucohydrolase, thioglucosidase or myrosinase enzymes (EC 3.2.1.147), play a role in increasing tolerance to biotic and abiotic stress factors. Furthermore, given their composition, they can serve as a nutrient reservoir under nutrient deficiency conditions.
 Limitations on study/implications: GSLs are synthesized only in species of the Capparidaceae, Brassicaceae, Resedaceae, and Moringaceae families.
 Findings/conclusions: GSLs are sulfur compounds that can serve as defense mechanisms against biotic and abiotic stress factors and as sources of nutrients in plants, and molecules with important nutraceutical properties in food and human health.

Determination of the limiting factors for sugarcane (Saccharum officinarum L.) productivity with Leaf Sampling Unit (LSU) method in sandy soil

Sugarcane is one of the important plantation commodities that is widely cultivated in Indonesia as a raw material for the sugar industry. One type of land that is commonly used for sugarcane cultivation is sandy soil, however, this soil has shortcomings due to nutrients availability which affects the productivity of sugarcane. This study aims to determine the limiting factor of sugarcane productivity in sandy soil through the Leaf Sampling Unit (LSU) analysis. Foliar nutrient levels of Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), and Magnesium (Mg) were determined. The parameters of plant growth observed included stalk height, stalk diameter, number of internodes per stalk, number of green leaves, number of stalk per clump, stalk fresh weight, and sugarcane productivity. Data were analyzed using correlation and descriptive tests. LSU analysis indicated that the levels of N and Ca were under sufficient conditions, at 1.98% and 0.33%, respectively. Meanwhile, the P, K, and Mg were in critical condition, with values of 0.03%, 0.09%, and 0.12%, respectively. Sugarcane stem diameter had a correlation with sugarcane productivity (r=0.985). Increasing the dose of fertilizers, especially P, K, and Mg is needed to overcome these nutrient deficiency conditions; thus the productivity of sugarcane can be optimized and sustainable.

Isolation and Characterization of Stress-Tolerant Priestia Species from Cowpea Rhizosphere Under Drought and Nutrient Deficit Conditions

This study aimed to isolate stress-tolerant phytobeneficial bacteria as bio-inoculants for cowpea's sustainable growth under drought and nutrient deficiency conditions. However, the application successful of phytobeneficial bacteria is subject to effective in vitro screening under different physiological conditions. We isolated several Priestia species from cowpea rhizosphere that tolerates polyethylene glycol (PEG6000)-induced drought and nutrient deficiency. Of them, C8 (Priestia filamentosa; basonym: Bacillus filamentosus), followed by C29 (Priestia aryabhattai; basonym: Bacillus aryabhattai), tolerated up to 20% PEG in a low-nutrient medium. In the presence of PEG, Priestia filamentosa and Bacillus aryabhattai exhibited optimal growth in different temperatures and pH but failed to survive at extreme temperatures of 45°C and pH 11. Priestia filamentosa preferred L-proline and L-glutamate, while L-tryptophan and L-tyrosine were the least utilized. Interestingly, Priestia filamentosa and Bacillus aryabhattai used more complex nitrogen sources, peptone, and yeast extract, than inorganic nitrogen for growth. Most importantly, under drought and nutrient deficiency, Priestia filamentosa exhibited multiple plant growth-promoting traits and more amylase and protease production than C29. Our results indicate that Priestia filamentosa is a potential bacterium to enhance the growth of cowpea plants under stressful conditions.

Challenges and obstacles implementing evidence-based food fortification policy in a high-income country.

The World Health Organization (WHO) recognizes food fortification as one of the most cost-effective and beneficial public health measures available. Mass fortification policies and regulations can reduce health disparities, including in high-income countries, by improving micronutrient intake among food-insecure or high-risk populations without changing their diet or behavior. While international health organizations have traditionally prioritized technical assistance and grants to medium and low-income countries, it is important to recognize that micronutrient deficiencies may also pose an important yet underappreciated public health problem in many high-income countries. Nevertheless, some high-income countries, including Israel, have been slow to adopt fortification, due to a variety of scientific, technological, regulatory, and political barriers. Overcoming these barriers requires an exchange of knowledge and expertise among the all stakeholders to achieve cooperation and broad public acceptance within countries. Similarly, sharing the experience of countries where the matter is in play may help inform efforts to advance fortification globally. Here we share a perspective on progress and barriers to achieve this goal in Israel, to inform efforts made to avoid the regrettable waste of unrealized human potential from prevalent yet preventable nutrient deficiency conditions, in Israel and beyond.

Alleviated environmental constraints and restructured fungal microbiome facilitate aggregate formation and stabilization in coastal mudflat saline soil amended by sewage sludge

AbstractSoil aggregates are important drivers of soil productivity. However, the relative importance of soil abiotic and biotic agents in driving aggregate formation and stabilization remain largely unexplored, especially in coastal mudflat saline soils. We amended saline soil with sewage sludge at rates of 0, 30, 75, and 150 t ha−1 to investigate the effects of sewage sludge on the particle size distribution and stability of soil aggregate and the underlying mechanisms induced by soil environmental factors and fungal community. Results revealed that the sewage sludge amendment significantly (p < 0.05) increased the proportion of macroaggregates with sizes larger than 0.25 mm (R0.25) and enhanced aggregate stability. Moreover, alleviation of saline‐alkali stress and nutrient (C, N, and P) deficiency conditions were significantly (p < 0.05) observed in sewage sludge‐amended soils. Additionally, restructured fungal communities in amended soils harbored significantly (p < 0.05) distinguishable structures and core and unique microbiomes. Particularly, fungal species belonging to Moterella significantly (p < 0.05) enriched in sludge reclaimed soils. Results derived from the random forest (RF) model accompanied by linear regression analysis revealed that soil pH, soil organic carbon, and fungal structural diversity were significantly (p < 0.05) related to aggregate composition (R0.25) and stability (geometric average diameter, GMD). Furthermore, fungal consortia composed of 20 closely interconnected operational taxonomic units (OTUs) affiliated with Ascomycota, Basidiomycota, and Zygomycota explained 28.36% and 49.88% variance of R0.25 and GMD, respectively. Overall, our results revealed the effect of sewage sludge on soil aggregation improvement in coastal areas and highlighted the respective importance of soil chemical properties and fungal microbiome in predicting aggregation status.

Spatial ionomics provides new insights into the accumulation and transport of mineral ions in rice (Oryza sativa L.) under Cadmium stress

The distribution of various elements in different organs is spatially specific, and the distribution of elements in different organs of rice under Cadmium (Cd) stress and nutrient deficiency conditions is unknown, these limit the creation of ideal crops. In this study, spatially-specific ionomics study was applied to the spatial distribution of ions in different organs of 14 different varieties of hybrid rice seedlings under Cd stress. Under Cd stress, magnesium (Mg), manganese (Mn), zinc (Zn), copper (Cu), and iron (Fe) were found to accumulate mainly in the nodes, while Ca accumulated mainly in the mature leaves, and K mainly in the leaf sheaths and new leaves. Under Cd stress, the contents of Mg and Mn in all organs and Mg, Mn, Zn, Ca, Cu, and Fe in nodes decreased, but the accumulation of Fe in roots increased. In all organs, the concentrations of calcium (Ca), Mg, Mn, and Fe were almost positively correlated. Moreover, the ion transfer factors of Mg/Mn, Mg/Cu, and Zn/potassium (K) all showed positive correlations, indicating that these elements had similar chemical properties or biological functions. The accumulation of Cd in different organs of 4 varieties under Cd stress and K/Mn/Ca/Mg deficiency treatments was studied. Under Mg deficiency stress, the Cd concentration increased significantly. Under Ca deficiency stress, Cd transport was reduced. In conclusion, spatial ionomics was used to investigate the transport and accumulation of elements in different organs of O. sativa L., and these results provided theoretical support for the creation and production of ideal crops under Cd stress.

Stearoyl CoA Desaturase-1 Silencing in Glioblastoma Cells: Phospholipid Remodeling and Cytotoxicity Enhanced upon Autophagy Inhibition.

Modulation of lipid metabolism is a well-established cancer hallmark, and SCD1 has been recognized as a key enzyme in promoting cancer cell growth, including in glioblastoma (GBM), the deadliest brain tumor and a paradigm of cancer resistance. The central goal of this work was to identify, by MS, the phospholipidome alterations resulting from the silencing of SCD1 in human GBM cells, in order to implement an innovative therapy to fight GBM cell resistance. With this purpose, RNAi technology was employed, and low serum-containing medium was used to mimic nutrient deficiency conditions, at which SCD1 is overexpressed. Besides the expected increase in the saturated to unsaturated fatty acid ratio in SCD1 silenced-GBM cells, a striking increase in polyunsaturated chains, particularly in phosphatidylethanolamine and cardiolipin species, was noticed and tentatively correlated with an increase in autophagy (evidenced by the increase in LC3BII/I ratio). The contribution of autophagy to mitigate the impact of SCD1 silencing on GBM cell viability and growth, whose modest inhibition could be correlated with the maintenance of energetically associated mitochondria, was evidenced by using autophagy inhibitors. In conclusion, SCD1 silencing could constitute an important tool to halt GBM resistance to the available treatments, especially when coupled with a mitochondria disrupter chemotherapeutic.

Quantitative Metabolomic Analysis of Changes in the Rat Blood Serum during Autophagy Modulation: A Focus on Accelerated Senescence.

Autophagy is involved in the maintenance of cellular homeostasis and the removal of damaged proteins and organelles and is necessary to maintain cell metabolism in conditions of energy and nutrient deficiency. A decrease in autophagic activity plays an important role in age-related diseases. However, the metabolic response to autophagy modulation remains poorly understood. Here, we for the first time explored the effects of (1) autophagy activation by 48 h fasting, (2) inhibition by chloroquine (CQ) treatment, and (3) combined effects of fasting and CQ on the quantitative composition of metabolites in the blood serum of senescent-accelerated OXYS and control Wistar rats at the age of 4 months. By means of high-resolution 1H NMR spectroscopy, we identified the quantitative content of 55 serum metabolites, including amino acids, organic acids, antioxidants, osmolytes, glycosides, purine, and pyrimidine derivatives. Groups of 48 h fasting (induction of autophagy), CQ treatment (inhibition of autophagy), and combined effects (CQ + fasting) are clearly separated from control groups by principal component analysis. Fasting for 48 h led to significant changes in the serum metabolomic profile, primarily affecting metabolic pathways related to fatty acid metabolism, and led to metabolism of several amino acids. Under CQ treatment, the most affected metabolites were citrate, betaine, cytidine, proline, tryptophan, glutamate, and mannose. As shown by two-way ANOVA, for many metabolites the effects of autophagy modulation depend on the animal genotype, indicating a dysregulation of metabolome reactivity in OXYS rats. Thus, the metabolic responses to modulation of autophagy in OXYS rats and Wistar rats are different. Altered metabolites in OXYS rats may serve as potential biomarkers of the manifestation of the signs of accelerated aging. Metabolic signatures characteristic to fasting and CQ treatment revealed in this work might provide a better understanding of the connections between metabolism and autophagy.

Differential metabolic rearrangements in the roots and leaves of Cicer arietinum caused by single or double nitrate and/or phosphate deficiencies.

Nitrate (NO3 - ) and phosphate (Pi) deficiencies are the major constraints for chickpea productivity, significantly impacting global food security. However, excessive fertilization is expensive and can also lead to environmental pollution. Therefore, there is an urgent need to develop chickpea cultivars that are able to grow on soils deficient in both NO3 - and Pi. This study focused on the identification of key NO3 - and/or Pi starvation-responsive metabolic pathways in the leaves and roots of chickpea grown under single and double nutrient deficiencies of NO3 - and Pi, in comparison with nutrient-sufficient conditions. A global metabolite analysis revealed organ-specific differences in the metabolic adaptation to nutrient deficiencies. Moreover, we found stronger adaptive responses in the roots and leaves to any single than combined nutrient-deficient stresses. For example, chickpea enhanced the allocation of carbon among nitrogen-rich amino acids (AAs) and increased the production of organic acids in roots under NO3 - deficiency, whereas this adaptive response was not found under double nutrient deficiency. Nitrogen remobilization through the transport of AAs from leaves to roots was greater under NO3 - deficiency than double nutrient deficiency conditions. Glucose-6-phosphate and fructose-6-phosphate accumulated in the roots under single nutrient deficiencies, but not under double nutrient deficiency, and higher glycolytic pathway activities were observed in both roots and leaves under single nutrient deficiency than double nutrient deficiency. Hence, the simultaneous deficiency generated a unique profile of metabolic changes that could not be simply described as the result of the combined deficiencies of the two nutrients.

Genome Editing Targets for Improving Nutrient Use Efficiency and Nutrient Stress Adaptation.

In recent years, the development of RNA-guided genome editing (CRISPR-Cas9 technology) has revolutionized plant genome editing. Under nutrient deficiency conditions, different transcription factors and regulatory gene networks work together to maintain nutrient homeostasis. Improvement in the use efficiency of nitrogen (N), phosphorus (P) and potassium (K) is essential to ensure sustainable yield with enhanced quality and tolerance to stresses. This review outlines potential targets suitable for genome editing for understanding and improving nutrient use (NtUE) efficiency and nutrient stress tolerance. The different genome editing strategies for employing crucial negative and positive regulators are also described. Negative regulators of nutrient signalling are the potential targets for genome editing, that may improve nutrient uptake and stress signalling under resource-poor conditions. The promoter engineering by CRISPR/dead (d) Cas9 (dCas9) cytosine and adenine base editing and prime editing is a successful strategy to generate precise changes. CRISPR/dCas9 system also offers the added advantage of exploiting transcriptional activators/repressors for overexpression of genes of interest in a targeted manner. CRISPR activation (CRISPRa) and CRISPR interference (CRISPRi) are variants of CRISPR in which a dCas9 dependent transcription activation or interference is achieved. dCas9-SunTag system can be employed to engineer targeted gene activation and DNA methylation in plants. The development of nutrient use efficient plants through CRISPR-Cas technology will enhance the pace of genetic improvement for nutrient stress tolerance of crops and improve the sustainability of agriculture.

Effect of inoculation with Acaulospora and Glomus on the growth and nutrition of blueberries (Vaccinium corymbosum) with different fertilization levels

In recent years, the global demand for blueberries has been growing because of its nutraceutical properties in the fruits, which provide important benefits to human health. Colombia, thanks to its diversity, has a great opportunity to meet the blueberry demands of the global markets. In the present study, the effect of two arbuscular mycorrhizal fungi (AMF) of the genera Glomus and Acaulospora were evaluated on the growth of blueberry plants var. Biloxi, subjected to three levels of chemical fertilization (100, 50 and 0%), with the 100% level being optimal. The blueberry plants inoculated with Glomus under conditions of nutrient deficiency (50AMF1+) increased dry mass, height, number of basal branches, leaf area, root/shoot ratio, and chlorophyll concentration, which were significantly higher than in the plants without inoculation with nutrient deficiency (0AMF- and 50AMF-). The plants inoculated with Glomus achieved an increase in height, while the plants inoculated with Acaulospora increased the number of basal branches when grown under a nutrient deficiency (50AMF+1) in relation to the uninoculated controls (0AMF- and 50AMF-). The results suggested that the best association of blueberry occurs with Glomus, with increased plant growth and nutrition (N, P, K, Ca, Mg, and S).

Structural and Predicted Functional Diversities of Bacterial Microbiome in Response to Sewage Sludge Amendment in Coastal Mudflat Soil.

Simple SummaryImproving microbial community and functional diversity is essential for the fertility activation and development of coastal mudflat soils, an important reserve resource for sustainable agricultural development. Although sewage sludge has been proven to be an effective agricultural practice to alleviate saline sodic stress and nutrient deficiency and thereby enable coastal mudflat reclamation, knowledge regarding the structural and functional diversities of bacterial microbiome in response to sewage sludge application remains unclear. In this study, we simultaneously investigated the effects of sewage sludge amendment on physicochemical characteristics, composition, diversity, and predicted function of bacterial community in coastal mudflat soil. Results revealed that both structural and functional diversities of bacterial microbiome were significantly improved due to microhabitat modification (i.e., mitigated saline–alkali and nutrient deficiency conditions) induced by sewage sludge amendment compared to untreated soil. Additionally, bacterial groups involved in cycling processes of carbon and nitrogen were significantly enriched in sewage sludge-amended mudflat soils. The current study enhanced our understanding of mechanisms underlying microbial community and functional diversities promoted by sewage sludge amendments.The study investigated the influence of sewage sludge application at rates of 0 (CK), 30 (ST), 75 (MT), and 150 (HT) t ha−1 to mudflats on bacterial community diversity and predicted functions using amplicon-based sequencing. Soils under sewage sludge treatments, especially the HT treatment, exhibited lower pH, salinity and higher nutrient contents (C, N, and P). Moreover, restructured bacterial communities with significantly higher diversities and distinct core and unique microbiomes were observed in all sewage sludge-amended soils as compared to the control. Specifically, core bacterial families, such as Hyphomicrobiaceae, Cytophagaceae, Pirellulaceae Microbacteriaceae, and Phyllobacteriaceae, were significantly enriched in sewage sludge-amended soils. In addition, sewage sludge amendment significantly improved predicted functional diversities of core microbiomes, with significantly higher accumulative relative abundances of functions related to carbon and nitrogen cycling processes compared to the unamended treatment. Correlation analyses showed that modified soil physicochemical properties were conducive for the improvement of diversities of bacterial communities and predicted functionalities. These outcomes demonstrated that sewage sludge amendment not only alleviated saline–sodic and nutrient deficiency conditions, but also restructured bacterial communities with higher diversities and versatile functions, which may be particularly important for the fertility formation and development of mudflat soils.

Role of Rhizosphere Soil Microbes in Adapting Ramie (Boehmeria nivea L.) Plants to Poor Soil Conditions through N-Fixing and P-Solubilization

The N-fixing and P-solubilization functions of soil microbes play a vital role in plant adaptation to nutrient-deficiency conditions. However, their exact roles toward the adaptation of ramie to poor soil conditions are still not clear. To fill this research gap, the N-fixing and P-solubilization efficiencies of soils derived from the rhizosphere of several ramie genotypes with different levels of poor soil tolerance were compared. Correlations between the N-fixing, P-solubilization efficiency, and the poor soil tolerable index were analyzed to quantify their contributions towards the adaptation of ramie plants to poor soil conditions. To explore how the microorganisms affected the potential of N-fixing/P-solubilization, the activities of the nutrients related the soil enzymes were also tested and compared. The results of this study confirm the existence of N-fixing and P-solubilization bacteria in the ramie rhizosphere of the soil. The number of N-fixing bacteria varied from 3010.00 to 46,150.00 c.f.u. per gram dry soil for the ramie treatment, while it was only 110.00 c.f.u. per gram dry soil for treatment without ramie cultivation. The average P-solubilization efficiency of ramie treatment was almost five times higher than that of the control soil (0.65 vs. 0.13 mg mL−1). The significant correlations between the poor soil tolerance index and the N-fixing bacteria number (r = 0.829)/nitrogenase activity (r = 0.899) suggest the significantly positive role of N-fixing function in the adaptation of ramie plants to poor soil. This is also true for P-solubilization, as indicated by the significant positively correlation coefficients between the ramie poor soil tolerance index and P-solubilization efficiency (0.919)/acid phosphatase activity (0.846). These characteristics would accelerate the application of “holobiont” breeding for improving ramie nutrient use efficiency.